<!DOCTYPE html>
<html>
  <head>
    <style>
      img:-moz-broken ~ label {color: green}
      label {color: red}
      img { display: none; }
    </style>
  </head>
  <body>
    <img src="no-such-scheme:nothing" id="ffximage"/>
    <label for="ffximage">Text should be green</label>
  </body>
</html>
